Taxonomic revision of the recent and holocene representatives of the Family Darwinulidae (Crustacea, Ostracoda), with a description of three new genera

The Darwinulidae, the only surviving family of the superfamily Darwinuloidea, are revised and 28 extant species are retained. Twenty-six species (2 of which as yet formally undescribed) are allocated to 5 genera, 3 of which are here described as new; 2 species have an uncertain position within the family because of their insufficient original description are listed here as species inquirendae. New genera are characterised on combinations of soft part and valve characters, but the chaetotaxy of the limbs seems most conservative and most suitable the identification of genera. Darwinula s.s. and Microdarwinula are, with regard to recent species, monospecific.Alicenula nov. gen. is erected to compromise the 3 species of the former serricaudata-group. Vesalenula nov. gen. comprises the 8 species of the pagliolii-boteaigroup, as well as Darwinula danielopoli, which, together with two undescribed species from Cuba and Tunisia, is placed in a special group within this new genus. Penthesilenula nov. gen. comprises two species-groups, with 10 species in total: 7 species in the incae-group, exclusively occurring in the southern Hemisphere, and 3 species in the africana-group. The latter group also contains P.malayica and P. brasiliensis, which occur on at least three continents; the latter species appears to have a higher indicence of morphological variability than the other extant darwinulids. The species-groups in the latter two genera are here used for convenience; no taxonomic value should at present be attached to them. Problems related to clonal taxonomy in general are briefly discussed. It is demonstrated that a systematic revision of an ancient asexual lineage can lead to a taxonomy which at the same time reflects natural phylogeny and is workable, i.e. is based on recognisable taxa.